After the shooting of President James A. Garfield by Charles J. Guiteau in Washington in 1881, one bullet remained lodged in his body, but doctors could not find it.
Garfield used to suffer a lot for about two months before his death. In the meantime, while trying to relieve the sick man from the heat of a Washington summer, engineers invented an early version of the modern air conditioner.
Moreover, Alexander Graham Bell devised a metal detector so as to find the bullet inside Garfield.
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